[en] OAK- B135 Operators of nuclear power plants face a significant challenge in designing the partly analog and partly digital (hybrid) control rooms that will be produced at various stages of plant instrumentation and control (I and C) modernization programs. This report provides the technical material for a five-unit training class to help meet the challenge of control room modernization

[en] A process of spinning a pitch having less than 40% by weight mesophase into a pitch fiber having at least 70% by weight mesophase is described

[en] The computer code, TRANS4, models the melting and penetration of a solid barrier by a solid disc of fuel following a core disruptive accident. This computer code has been used to model fuel debris penetration of basalt, limestone concrete, basaltic concrete, and magnetite concrete. Sensitivity studies were performed to assess the importance of various properties on the rate of penetration. Comparisons were made with results from the GROWS II code

[en] The reactivity feedback from fuel relocation is a central issue in the analysis of loss-of-flow (LOF) accidents in LMFBRs. Fuel relocation has been studied in a number of LOF simulations in the TREAT reactor. In this paper the results of these tests are analyzed, using, as the principal figure of merit, the changes in equivalent fuel worth associated with the fuel motion. The equivalent fuel worth was calculated from the measured axial fuel distributions by weighting the data with a typical LMFBR fuel-worth function. At nominal power, the initial fuel relocation resulted in increases in equivalent fuel worth. Above nominal power the fuel motion was dispersive, but the dispersive driving forces could not unequivocally be identified from the experimental data

[en] The Site Deactivation and Decommissioning (SDD) Organization is evaluating options to disposition the 800 underground tanks (including removal of the sludge heels from these tanks). To support this effort, DandD requested assistance from Savannah River National Laboratory (SRNL) personnel to determine the pertinent physical properties to effectively mobilize the sludge from these tanks (Tanks 804, 808, and 809). SDD provided SRNL with samples of the sludge from Tanks 804, 808, and 809. The authors measured the following physical properties for each tank: particle settling rate, shear strength (i.e., settled solids yield stress), slurry rheology (i.e., yield stress and consistency), total solids concentration in the sludge, soluble solids concentration of the sludge, sludge density, and particle size distribution

[en] Pancreatic polypeptide (PP) and peptide YY (PYY) are inhibitors of pancreatic exocrine secretion in vivo but not in vitro, which suggests intermediate mechanisms of action. To examine the role of pancreatic blood flow in these inhibitory effects, xenon-133 gas clearance was used to measure pancreatic blood flow while simultaneously measuring pancreatic exocrine secretion. PP or PYY (400 pmol/kg/h) was administered during the intermediate hour of a 3-h secretin (125 ng/kg/h)/cholecystokinin octapeptide (CCK-8) (50 ng/kg/h) infusion. Exocrine secretion and pancreatic blood flow during the PP or PYY hours were compared with that observed in the first and third hours of the secretin/CCK-8 infusion. PP and PYY significantly inhibited secretin/CCK-8-induced pancreatic exocrine secretion. In addition, PYY (but not PP) significantly reduced pancreatic blood flow during secretin/CCK-8 stimulation. Nevertheless, there was no correlation between pancreatic blood flow and bicarbonate or protein outputs. It is concluded that changes in pancreatic blood flow do not mediate the inhibitory effects of PP or PYY on the exocrine pancreas

No abstract available

[en] During aerosol testing conducted by Parsons Constructors and Fabricators, Inc. (PCFI), air sparger plugging was observed in small-scale and medium-scale testing. Because of this observation, personnel identified a concern that the steam spargers in Pretreatment Facility vessel UFP-02 could plug during Waste Treatment and Immobilization Plant (WTP) operation. The U. S. Department of Energy (DOE) requested that Savannah River National Laboratory (SRNL) provide consultation on the evaluation of known WTP bubbler, and air and steam sparger issues. The authors used the following approach for this task: reviewed previous test reports (including smallscale testing, medium-scale testing, and Pretreatment Engineering Platform [PEP] testing), met with Bechtel National, Inc. (BNI) personnel to discuss sparger design, reviewed BNI documents supporting the sparger design, discussed sparger experience with Savannah River Site Defense Waste Processing Facility (DWPF) and Sellafield personnel, talked to sparger manufacturers about relevant operating experience and design issues, and reviewed UFP-02 vessel and sparger drawings

No abstract available

[en] Measurement of pancreatic blood flow (PBF) is technically demanding. Although radiolabeled microspheres are considered the gold standard for PBF assessment, they have practical limitations. In the current study, H₂ and xenon-133 gas clearance techniques were adapted to PBF measurement and compared to radiolabeled microsphere techniques. Simultaneous measurements of PBF were made using either hydrogen or xenon gas washout and radiolabeled microspheres. Measurements were made under basal, vasoconstricted (vasopressin 2U i.v. or nicotine 4 micrograms/kg/h) and stimulated (secretin 125 ng/kg/h or 2 U/kg i.v.) conditions (random order). Mean PBF was 26.9 +/- 5.3, 50.5 +/- 2.3 and 27.6 +/- 5.2 ml/min/100 g basally, 36.9 +/- 8.0, 90.1 +/- 18.9, and 81.7 +/- 14.5 ml/min/100 g in the stimulated state, and 24.2 +/- 7.8, 25.0 +/- 3.5, and 14.9 +/- 7.5 ml/min/100 g in the vasoconstricted state for hydrogen gas clearance, xenon gas clearance, and radiolabeled microspheres, respectively. The H₂ clearance technique resulted in tissue trauma, was complicated by frequent electrode displacement, and correlated poorly (r2 = 0.36, p greater than 0.05) with microsphere values. In contrast, xenon clearance measurement had no apparent effect on the pancreas and correlated well (r2 = 0.83, p less than 0.01) with microsphere data. We conclude that xenon clearance offers an attractive, validated alternative to radiolabeled microspheres for measuring pancreatic blood flow